The use of lasers in surgery has grown dramatically in the past ten years. In particular, the use of the CO.sub.2 laser in surgery has grown from a very limited range of applications in the mid-1970s to become a widely used tool for a variety of surgical procedures in virtually every major surgical specialty. During this time, however, the instruments used by surgeons in conjunction with lasers, such as forceps and clamps, remained essentially unchanged.
In addition to medical applications, lasers are increasingly used in various manufacturing procedures. For example, lasers can be used for welding in the assembly of micro-electronic components. Special tools are often required in such procedures.
Instruments used in laser surgery are in most respects of the same type as those used in more conventional surgery. However, special properties are required of instruments used in laser surgery. One of the principle requirements is that the instrument not reflect the laser beam if the beam inadvertently or unavoidably strikes the instrument. If the laser beam is reflected, there is the likelihood that the patient or even the surgeon or his assistants may be injured by the reflected beam. This non-reflective requirement makes standard stainless steel surgical instruments unsuited for laser surgery.
Previously, attempts have been made to manufacture instruments which were both non-reflective and still functional in their intended use. Glass instruments, which absorb the infrared radiation used in laser surgery, have been tried without success. Under the heat loads generated by the laser beam, glass instruments are prone to cracking and breaking leading to the dangerous possibility of portions of the instrument being lost within the incision. In addition, sturdy glass instruments are difficult to fabricate in the variety of intricate shapes required for the various surgical techniques.
Wooden instruments have also been used in laser surgery. Aside from the difficulty of fabricating complex instruments, the danger of fire exists when wooden instruments are exposed to an infrared laser beam. Other materials have been tested, including specially annealed glasses, plastics, oxidized and dioxidized metals. These materials have been found lacking due to poor mechanical or chemical characteristics.
Perhaps the most successful, to date, non-reflective instruments are anodized stainless steel or titanium instruments. These instruments, although the best current alternatives and widely used, suffer a number of serious drawbacks. The anodized coating scratches easily and small portions of it can be left in the wound. Anodization is an oil base process and toxic fumes generated when the instrument is subjected to the high temperatures generated by the laser beam are a hazard. Anodization reduces reflection by only 45% to 50% and the reflected beam is not diffused in nature. Even if the instrument is sand blasted prior to anodization, the anodization process glazes over the surface and the reflected beam is specular in nature.
In summary, a suitable instrument for laser surgery must be non-reflective and possess sufficient structural and chemical integrity to withstand the demands placed upon it by the surgeon's manipulations, the heat generated by the laser beam, and the normal wear and tear of hospital cleaning and sterilizing. In addition, it is desirable that the instrument possess a similar heft and balance to conventional instruments so that the surgeon feels comfortable in using the instrument.
Tools and instruments for use in non-medical applications must exhibit similar properties. The tools must be non-reflective and at the same time retain their ability to function in their intended use.
The instruments of the present invention are the first instruments to meet these requirements. They are non-reflective and still retain their inherent value as tools. The instruments of the instant invention are resistant to corrosion, have good wear properties, high mechanical strength at high temperatures and are easily sterilized. They may be fabricated in any of the myriad of shapes and forms required. Finally, there is little difference, if any, in the feel of these new instruments when compared to conventional surgical instruments.